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Today, Intel has unveiled its next-generation Atom CPU core. Called Silvermont, this 22nm CPU will power the Merrifield (smartphone) and Bay Trail (tablet) SoCs. While its predecessor, Saltwell (Medfield & Clover Trail), was the first Intel chip to earn a place at the mobile table, Silvermont is the first product released by Intel that should take the performance and performance-per-watt crowns from ARM designs made by Qualcomm, Nvidia, Apple, and Samsung. With the PC market waning, and investors flocking to competitors with proven mobile designs, Silvermont is a very, very big deal for Intel. Is a fast mobile x86 CPU enough to save a floundering Windows tablet market, though, or are the other endemic issues at play?

Silvermont is Intel’s first new Atom microarchitecture in five years, and it has been rearchitected from the ground up to provide excellent performance, while sipping fewer watts than its ARM-based cousins. One of the most significant changes was the shift to 22nm FinFET, which really blows the doors off any competing process technologies as far as power consumption goes. Combined with the shift to 3D transistors, Silvermont’s architecture and design were actually co-optimized with the process. The ability to design a specific process for a specific CPU core is one of the main reasons that Intel holds such a dominant position over companies such as Qualcomm and Nvidia, who have to work with TSMC’s one-size-fits-all 28nm processes.

Beyond the new process, Silvermont has a slew of new features that should improve power efficiency and performance over the Saltwell core. There’s out-of-order execution (OoOE), which allows for instructions to be executed as soon as there’s data to be processed, rather than in the exact order laid out by the software program. There’s more efficient branch processing, more accurate branch predictors, and faster recovery from pipeline crashes/collisions. In terms of additional instructions, Silvermont borrows a lot of features from Westmere (the die shrink of Nehalem). There’s AES-NI (hardware-level encryption/decryption), Secure Key (random number generation), and SSE4.1 and 4.2.

Saltwell vs. Silvermont pipeline changes. The change from 10 to 13-cycle mispredict is very nice.

One of the biggest performance boosts is likely to stem from massively improved FPU latency and throughput: Silvermont executes many instructions in half the time, while throughput has almost doubled. If you ever lamented the x87 FPU performance of previous Atom cores, be cheered: Silvermont’s FPU performance should be comparatively beastly.

Rounding out the architectural changes, there’s also some high-bandwidth/low-latency caches and out-of-order memory transactions. For a complete rundown of the new microarchitecture, you can attempt to interpret the core block diagram below. In short, though, Silvermont gets more done per clock cycle (IPC), and it uses much less power to perform each clock cycle. While no one actually has any Silvermont hardware to independently benchmark, Intel is claiming a ~3x performance improvement at ~5x lower power, over current Saltwell (Medfield/Clover Trail) Atom chips.

Silvermont’s core block diagram

Moving from the micro to the macro scale, Silvermont finally brings real multi-core support to Atom. Somewhat like AMD’s Bulldozer, Silvermont comes in modules of two cores, which share a tightly coupled up-to-1MB L2 cache. An Atom SoC can contain up to four modules, for a total of eight Silvermont cores. There’s per-core frequency and power management — but there’s no Hyper-Threading. On the performance front, Burst Mode (Atom’s version of Turbo Boost) has been souped up: Whereas Atom used to just base its P-states (SpeedStep) on core temperature, Silvermont manages Burst frequency by analyzing thermal, electrical, and power delivery constraints. Silvermont can also dynamically share/allocate power between CPU cores and the GPU, which is obviously rather neat for mixed workloads.

The end result of all this work is best summarized with an almost unbelievable graph:

What you don’t see is the small print at the bottom of each slide, warning us that Intel may have used benchmarks that are “optimized for performance only on Intel microprocessors.” Caveats and loaded dice aside, though, it does seem like Silvermont will be very frugal in the power consumption department. It will be very exciting when Intel actually starts shipping dev kits that we can independently benchmark.

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Jamie MacDonald

Wow, is it ET or Intel that pays your wages?

Snipes

Ya man, comprehensive analysis of new technology has no place on Extreme Tech.

Xplorer4x4

My guess is he was referring to the sensationalized headline. “Intel ready to crush arm,” and while that looks possible performance wise, the article itself starts backtracking to the fact that in the SoC market, power consumption is one of the biggest goals/obstacles for Intel which is something they have not released and we have no real world benchmarks for yet. Thus Intel may not be quite ready to crush the competition just yet, not where it matters most.

tgrech

If you class this as comprehensive, then what the hell is Charlie’s 3500+ word evaluation on the Silvermont architecture alone? Sebastian did well to tackle the more economic side of things, and kept the article more interesting to those who don’t want a deep explanation on why the L1 cache(Amongst other things) is slightly more efficient, but I wouldn’t call it a “comprehensive analysis of new technology”.

Um, yeah its called Marketing. It’s nothing new. It has gone on for as long as the electronics market has been around I would guess. Granted it may be a bit more skewed today when you jump from x2.325 to 3 rather then say 2.5 but typical marketing from any company showcasing a new product. If you want the truly accurate scoop, then take everything from any OEM with a grain of salt and stick to the likes of ET or S|A for the exact numbers.

tgrech

Yeah I understand why a marketing team would do this, but it wasn’t a marketing team. Intel themselves never said ~3x faster and made such a crazy jump, Sebastian did, I’m just wondering why he himself would supposedly twist the numbers so greatly rather than just give us the original figures or image. It’s bad enough that these results are probably bias anyway(Since they come straight from Intel).

philtheone

You lost me at “. . . FPU performance should be beastly.” I could not continue to read while laughing. . .

greybirdtoo

Yeah, me too. I’m not sure Sebastian knows that in traditional parlance, “beastly” means unpleasant or nasty. The only place I know where it’s different is when repeated the “Urban Dictionary” says “beastly beastly” means “friggin’ cool.”

doubledeej

On many occasions I’ve believed Intel when they’ve claimed that a new architecture for Atom fixes the performance issues. And every time they have really let us down. Never again.

http://www.facebook.com/profile.php?id=1223563048 Angel Ham

I would be laughing hard if it turns out that this chip outperforms an AMD Jaguar chip in terms of CPU performance. I can’t wait for the benchmark results and then use them to troll the PS4Durango fans mwahahaha.

Marc Guillot

Its GPU has no chance to compete with PS4 SoC’s GPU.

http://www.facebook.com/profile.php?id=1223563048 Angel Ham

I know that. The gaming sites are loaded with comments on how the Wii U is an underperforming machine so I’m going to use the benchmarks (if it does what I’m hoping for) to rub it on their faces on how their precious PS machine went from having an i7 equivalent to two tablet processors glued together.

Marc Guillot

You can do that, and you’ll be right, but you know that that’s only trolling. What matters most on games are GPU’s.

veteran_gamer

The speed of the processor will become insignificant once GaiKai takes off. You could have PS4s with Pentium processors, and it would not make a blind bit of difference. The future of gaming is streaming, why would Sony release such an apparently ‘underpowered’ console, considering their penchant for game related rhetoric. Who can forget the ‘Emotion Engine’, the ‘Reality synthesizer’, or the ‘Cell Broadband Engine’. Sony seem to have forgotten to release an equally appealing epitaph, perhaps because the console is no longer the focus, perhaps it is the service. Try not to live in the past, by comparing values that hold no relevance. It is the experience that counts, not the gigahertz!

eliking

We’ll see what happens. Competition is good, but Intel is under a lot of constraints that may make it hard for it to succeed. It needs to be careful of not delivering too much performance on Windows 8 tablet side, otherwise it will cannibalize much much more profitable Core chip sales. Intel shareholders also demand high margins, which will make it difficult to win share by cutting prices. It will have to compete directly with several ARM vendors willing to under-price it. For an ARM vendor, 30% margin is decent, but for Intel, it would be an embarrassment. It will want to position it as a high end product to extract a higher price than competition, but high end is occupied by Apple and Samsung, and they make their own chips. The rest are mainly just struggling to get by and just want the cheapest “good enough” chip they can get.

http://www.facebook.com/nick.babouras Γιάννης Σαμολαδάς

” If Microsoft couldn’t get the Surface RT below $500 with an ARM processor inside “
FYI, there is a Asus Windows RT tablet that is priced at $357 on Amazon.

” Silvermont isn’t going to magically conjure up a Metro app ecosystem “
Doesn’t have to. x86 runs everything you have on your PC. That’s why the Surface Pro is more popular (based on Amazon user reviews) than Surface RT despite the steeper price.

Jml

And IT STILL SUCKS EGGS!!!!!! NOW DIE M$ DIE!!!!!!! DIE AMD DIE NOW!!!!!!

raddude9

microsoft will be fine if they release a new version of windows 8, and AMD is doing fine, they’ve turned the corner financially and are bringing out some nice new chips.

Jml

Somehow I don’t believe you on that. M$ is in trouble their Xbox 720 sucks, M$ windows 8 sucks, and they have no hope in tablet/phone markets they are FINISHED!!! AMD needs a miracle to survive and Temash IS NOT IT nor will Kaveri be that Miracle. Kaveri was AMD only chance for survival and now its going to disappoint like no tomorrow and because of that fact AMD is going to die.

raddude9

Short term microsoft will be fine, they have so many business customers. Long term could be different.

Nope, you’re wrong about AMD yet again, they have some solid new chips and are not going to die any time soon.

Jml

AMD does NOT have ANY solid chips they ALL suck compared to Intel’s almighty Haswell!!!!!

raddude9

Almighty expensive Haswell you mean.

Jml

Also true.

SPM

“FYI, there is a Asus Windows RT tablet that is priced at $357 on Amazon”

That’s on clearance firesale pricing though – due to Windows RT tablets not selling. There will be a big loss associated with that price level.

Arkhimedean

“Intel’s mobile chief told me in an interview, ‘Windows
8 on tablets, Android on smartphones. Right now, I have as many people
working on Windows 8 tablets as I have on Android phones'”

Keep in mind that this comment was made a year ago, before Windows 8 tanked. How difficult can it be to reassign Android phone teams to work on Android tablets anyway?

Marc Guillot

I’ve seen Intel promising to crush ARM for years.

I won’t believe in these Intel commercials, and wait for the real product.

Roberto Tomás

I don’t even buy the prima fascia case for Atom here .. they aren’t comparing it to current gen snapdragon 600/800’s or tegra 4s, they are comparing them to older A9 dual cores and quad cores (low-clock tegra 3s). That means that Silvermont will likely barely be on par with Tegra 4.
Six months or so later they will be competing with 16nm A57s, which should easily double compute while halving power consumption, plus integrate with mainstream peripheral components like storage and ram. In short, even if Airmont doubles the performance again, Intel will find it hard to compete in it’s chosen metric, which agreeably doesn’t matter so much anymore: raw compute.

Yep, seems very light on the actual real world performance and power specs and even if its better than the usual Android CPU’s, will it compete on price. Just recently I bought a generic 4 core Android 10 inch tablet for $250. It has the usual 5+ hours of moderate processing use but the most interesting and for me important feature is its ability to get up and running within seconds from powering up. No Intel/Windows combo comes even close even with SSD drives and as for windows net-books, they’re slugs when it comes to firing up. . I guess we’ll have to wait and see just what Intel has achieved and whether its too little too late or unnecessary for a market place that has already matured.

Greg Giese

I definitely know a LOT of people that choose their phone and tablets based on the processor that’s in it…..NOT

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